Claire E Couch, PhD
Claire Couch is an ecologist who studies fish behavior, health, and physiology. The purpose of her research is to monitor threatened fish populations and support recovery and reintroduction efforts. Prior to joining WFRC, Claire was faculty at Oregon State University.
Claire has a broad background in ecology and biology. Early in her career, she spent time working on bacterial genetics and vaccine development with the National Institutes of Health. She then spent several years studying disease ecology in large herbivores during her PhD. Claire began studying salmon during her postdoc and has been working with salmonids ever since.
Initially, Claire’s salmon research focused on prespawning mortality in adult salmon and the health of juvenile fish in hatcheries. She worked with pathologists and parasitologists to identify diseases that
may be linked to pre-spawning mortality. She also studied the effects of rearing conditions on juvenile fish microbiomes and disease susceptibility. Ultimately, this work led her to become more broadly interested in salmon population recovery and reintroduction.
Currently, Claire uses a variety of laboratory, field-based, and analytical approaches to study how river impoundments (dams and reservoirs) alter fish migration, ecology, and physiology. Most of her work is designed to support the recovery and/or reintroduction of fish populations in partnership with Tribal, State, and Federal partners.
Professional Experience
2024-Present – Biologist, U.S. Geological Survey, Western Fisheries Research Center, Columbia River Research Laboratory, Cook, WA
2023-2024 – Assistant Professor (Senior Research), Oregon State University, Corvallis, OR
2022-2023 – Research Associate and Instructor, Oregon State University, Corvallis, OR
2020-2022 – Postdoctoral Scholar, Oregon State University, Corvallis, OR
2015-2020 – PhD Student, Oregon State University, Corvallis, OR
2014-2015 – Postbaccalaureate Intramural Research Trainee, National Institutes of Allergy and Infectious Disease, Rocky Mountain Laboratory, Hamilton, MT
Education and Certifications
PhD. 2020. Integrative Biology, Oregon State University, Corvallis, OR
BS. 2013. Biology, University of Portland, Portland, OR
Science and Products
Evaluation of pathogen risks and testing considerations for Chinook salmon egg movements between New Zealand and California Evaluation of pathogen risks and testing considerations for Chinook salmon egg movements between New Zealand and California
Executive Summary Oncorhynchus tshawytscha (Walbaum in Artedi, 1792; Chinook salmon) were historically abundant in the McCloud River but are now extirpated from this tributary owing to dam construction and lack of passage. Planning efforts to restore populations above Shasta and Keswick Dams are currently underway, including an evaluation of potential source populations. One potential...
Authors
Claire E. Couch, David B. Powell, Jan Lovy
Laboratory transmission of adult salmon enteritis and associated pathogens in juvenile Chinook salmon (Oncorhynchus tshawytscha) Laboratory transmission of adult salmon enteritis and associated pathogens in juvenile Chinook salmon (Oncorhynchus tshawytscha)
Adult salmon enteritis (ASE), characterised by severe ulcerative enteritis, has been linked to prespawn mortality (PSM) in spring Chinook salmon (Oncorhynchus tshawytscha) in certain rivers in Oregon, USA. Catastrophic losses of spring Chinook salmon have resulted from PSM, a significant threat to their population stability. Understanding the causes of ASE is therefore critical for...
Authors
Tamsen Polley, Claire E. Couch, Connor Leong, James T. Peterson, Louis M. Weiss, Peter M. Takvorian, Michael L. Kent
Editorial: Parasite, host, and microbiome interactions in natural host systems Editorial: Parasite, host, and microbiome interactions in natural host systems
No abstract available.
Authors
Claire E. Couch, Raquel Xavier, Brianna R. Beechler
Unique diet and Philonema sp. infections in reservoir-rearing juvenile Chinook Salmon Unique diet and Philonema sp. infections in reservoir-rearing juvenile Chinook Salmon
Objective Dams and reservoirs can alter juvenile growth and survival of migratory salmonids through several physical and biological mechanisms. Juvenile Chinook Salmon Oncorhynchus tshawytscha that are produced upstream of large hydropower dams may have associated passage mortality, but the reservoirs created by these dams can support rapid growth. Characterizing the biotic drivers of...
Authors
Marina S. Larson, Anindo Choudhury, Ethan N. Gardner, Peter Konstantinidis, Christina Amy Murphy, Michael L. Kent, James T. Peterson, Claire E. Couch
Gut microbiome composition associates with corticosteroid treatment, morbidity, and senescence in Chinook salmon (Oncorhynchus tshawytscha) Gut microbiome composition associates with corticosteroid treatment, morbidity, and senescence in Chinook salmon (Oncorhynchus tshawytscha)
Pacific salmon experience prolonged elevation in corticosteroid hormones during important life history events including migration, reproduction, and senescence. These periods of elevated corticosteroids correspond with changes to immunity and energy metabolism; therefore, fish may be particularly vulnerable to mortality at these times. Recent studies found that stress-induced cortisol...
Authors
Claire E. Couch, William T. Neal, Crystal L. Herron, Michael L. Kent, Carl B. Schreck, James T. Peterson
Effects of supplemental feeding on the fecal bacterial communities of Rocky Mountain elk in the Greater Yellowstone Ecosystem Effects of supplemental feeding on the fecal bacterial communities of Rocky Mountain elk in the Greater Yellowstone Ecosystem
Supplemental feeding of wildlife is a common practice often undertaken for recreational or management purposes, but it may have unintended consequences for animal health. Understanding cryptic effects of diet supplementation on the gut microbiomes of wild mammals is important to inform conservation and management strategies. Multiple laboratory studies have demonstrated the importance of...
Authors
Claire E Couch, Benjamin Wise, Brandon Scurlock, Jared D. Rogerson, Rebecca K. Fuda, Eric K Cole, Kimberly E Szcodronski, Adam Sepulveda, Patrick R. Hutchins, Paul C. Cross
Non-USGS Publications**
Polley, Tamsen & Couch, Claire & Leong, Connor & Peterson, James & Weiss, Louis & Takvorian, Peter & Kent, Michael. (2025). Laboratory transmission of Adult Salmon Enteritis and associated pathogens in juvenile Chinook Salmon (Oncorhynchus tshawytscha). 10.1101/2025.04.07.647091.
Carey, K. C., Kent, M., Schreck, C. B., Couch, C. E., Whitman, L., & Peterson, J. T. (2024). Influence of stream temperature and human disturbance on prespawn mortality of Chinook Salmon in the Willamette River basin. North American Journal of Fisheries Management, 44(5), 1147-1164.
Mani, A., Henn, C., Couch, C., Patel, S., Lieke, T., Chan, J. T., ... & Salinas, I. (2024). A brain microbiome in salmonids at homeostasis. Science Advances, 10(38), eado0277.
Schuster, C. J., Murray, K. N., Sanders, J. L., Couch, C. E., & Kent, M. L. (2024). Review of Pseudoloma neurophilia (Microsporidia): A common neural parasite of laboratory zebrafish (Danio rerio). Journal of Eukaryotic Microbiology, 71(5), e13040.
Tsuchida, D. Y., Gentzkow, M. F., Spaan, R. S., Burco, J., Couch, C. E., Spaan, J. M., ... & Beechler, B. R. (2024). Bighorn Sheep (Ovis canadensis) with Higher Whole Blood Selenium Levels Have Improved Survival and Altered Immune Responses. The Journal of Wildlife Diseases, 60(3), 721-726.
Larson, M. S., Choudhury, A., Gardner, E. N., Konstantinidis, P., Murphy, C. A., Kent, M. L., ... & Couch, C. E. (2024). Unique diet and Philonema sp. infections in reservoir‐rearing juvenile Chinook Salmon. Transactions of the American Fisheries Society, 153(3), 312-325.
Couch, C., Sanders, J., Sweitzer, D., Deignan, K., Cohen, L., Broughton, H., ... & Beechler, B. (2022). The relationship between dietary trophic level, parasites and the microbiome of Pacific walrus (Odobenus rosmarus divergens). Proceedings of the Royal Society B, 289(1972), 20220079.
Laliberte, C., Devan-Song, A., Burco, J. D., Couch, C. E., Gentzkow, M. F., Spaan, R. S., ... & Beechler, B. R. (2023). A simple biochemical plasma test as an indicator of maternal energy balance predicts offspring survival in bighorn sheep. Frontiers in Ecology and Evolution, 11, 1106635.
Couch, C. E., Neal, W. T., Herron, C. L., Kent, M. L., Schreck, C. B., & Peterson, J. T. (2023). Gut microbiome composition associates with corticosteroid treatment, morbidity, and senescence in Chinook salmon (Oncorhynchus tshawytscha). Scientific Reports, 13(1), 2567.
Couch, C. E., Peterson, J. T., & Heimowitz, P. (2023). Evaluating the institutional and ecological effects of invasive species prevention policy: a case study from the US Fish and Wildlife Service. Management of Biological Invasions, 14(2), 269-288.
Couch, C. E., Colvin, M. E., Chitwood, R. L., Peterson, J. T., & Schreck, C. B. (2022). Scope of the cortisol stress response in Chinook salmon during maturation. Fisheries Research, 254, 106416.
Schuster, C. J., Sanders, J. L., Couch, C., & Kent, M. L. (2022). Recent advances with fish microsporidia. In Microsporidia: Current Advances in Biology (pp. 285-317). Cham: Springer International Publishing.
Yarborough, E., Glidden, C., Coon, C., Couch, C., Sisson, D., Johns, J., ... & Beechler, B. (2022). Exploring the use of the erythrocyte sedimentation rate as an inflammatory marker for free-ranging wildlife: a case study in african buffalo (syncerus caffer). The Journal of Wildlife Diseases, 58(2), 298-308.
Couch, C. E., Kent, M. L., Weiss, L. M., Takvorian, P. M., Nervino, S., Cummins, L., & Sanders, J. L. (2022). Enterocytozoon schreckii n. sp. infects the enterocytes of adult chinook salmon (Oncorhynchus tshawytscha) and may be a sentinel of immunosenescence. Msphere, 7(1), e00908-21.
Couch, C. E., & Epps, C. W. (2022). Host, microbiome, and complex space: applying population and landscape genetic approaches to gut microbiome research in wild populations. Journal of Heredity, 113(3), 221-234.
Rothenberg, S. E., Sweitzer, D. N., Rackerby, B. R., Couch, C. E., Cohen, L. A., Broughton, H. M., ... & Beechler, B. R. (2021). Fecal methylmercury correlates with gut microbiota taxa in Pacific walruses (Odobenus rosmarus divergens). Frontiers in Microbiology, 12, 648685.
Couch, C. E., Stagaman, K., Spaan, R. S., Combrink, H. J., Sharpton, T. J., Beechler, B. R., & Jolles, A. E. (2021). Diet and gut microbiome enterotype are associated at the population level in African buffalo. Nature communications, 12(1), 2267.
Yang, C., Kari, L., Lei, L., Carlson, J. H., Ma, L., Couch, C. E., ... & Caldwell, H. D. (2020). Chlamydia trachomatis plasmid gene protein 3 is essential for the establishment of persistent infection and associated immunopathology. MBio, 11(4), 10-1128.
Couch, C. E., Arnold, H. K., Crowhurst, R. S., Jolles, A. E., Sharpton, T. J., Witczak, M. F., ... & Beechler, B. R. (2020). Bighorn sheep gut microbiomes associate with genetic and spatial structure across a metapopulation. Scientific reports, 10(1), 6582.
Couch, C. E., Movius, M. A., Jolles, A. E., Gorman, M. E., Rigas, J. D., & Beechler, B. R. (2017). Serum biochemistry panels in African buffalo: Defining reference intervals and assessing variability across season, age and sex. PLoS One, 12(5), e0176830.
Yang, C., Kari, L., Sturdevant, G. L., Song, L., Patton, M. J., Couch, C. E., ... & Caldwell, H. D. (2017). Chlamydia trachomatis ChxR is a transcriptional regulator of virulence factors that function in in vivo host–pathogen interactions. Pathogens and Disease, 75(3), ftx035.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Historical (1900s-1940s) and present-day (2003 – 2023) spring Chinook salmon (Oncorhynchus tshawytscha) spawning distribution in the Willamette River Basin, Oregon Historical (1900s-1940s) and present-day (2003 – 2023) spring Chinook salmon (Oncorhynchus tshawytscha) spawning distribution in the Willamette River Basin, Oregon
Spawning distribution maps for Upper Willamette River (UWR) spring Chinook salmon were created for the historical period (approximately 1910-1940), and for the present-day period (2003-2023). These maps were created as a tool to visualize generalized, reach-scale patterns of spawning distribution before and after the construction of high-head dams and other large-scale anthropogenic...
Acoustic-tagged juvenile Chinook salmon (Oncorhynchus tshawytscha), steelhead (O. mykiss), and sockeye salmon (O. nerka) detections in the Yakima River, Washington, 2018-2024 (version 1.1, September 2025) Acoustic-tagged juvenile Chinook salmon (Oncorhynchus tshawytscha), steelhead (O. mykiss), and sockeye salmon (O. nerka) detections in the Yakima River, Washington, 2018-2024 (version 1.1, September 2025)
Juvenile Chinook salmon (age 0 and age 1), steelhead, and sockeye salmon were tagged with acoustic transmitters and released at sites along the Yakima River in and below Yakima, WA from 2018 to 2024. Detection sites varied across years but included arrays placed at diversion dams, canals, hydropower facilities, and other locations throughout the Yakima and Columbia rivers. Study design...
Science and Products
Evaluation of pathogen risks and testing considerations for Chinook salmon egg movements between New Zealand and California Evaluation of pathogen risks and testing considerations for Chinook salmon egg movements between New Zealand and California
Executive Summary Oncorhynchus tshawytscha (Walbaum in Artedi, 1792; Chinook salmon) were historically abundant in the McCloud River but are now extirpated from this tributary owing to dam construction and lack of passage. Planning efforts to restore populations above Shasta and Keswick Dams are currently underway, including an evaluation of potential source populations. One potential...
Authors
Claire E. Couch, David B. Powell, Jan Lovy
Laboratory transmission of adult salmon enteritis and associated pathogens in juvenile Chinook salmon (Oncorhynchus tshawytscha) Laboratory transmission of adult salmon enteritis and associated pathogens in juvenile Chinook salmon (Oncorhynchus tshawytscha)
Adult salmon enteritis (ASE), characterised by severe ulcerative enteritis, has been linked to prespawn mortality (PSM) in spring Chinook salmon (Oncorhynchus tshawytscha) in certain rivers in Oregon, USA. Catastrophic losses of spring Chinook salmon have resulted from PSM, a significant threat to their population stability. Understanding the causes of ASE is therefore critical for...
Authors
Tamsen Polley, Claire E. Couch, Connor Leong, James T. Peterson, Louis M. Weiss, Peter M. Takvorian, Michael L. Kent
Editorial: Parasite, host, and microbiome interactions in natural host systems Editorial: Parasite, host, and microbiome interactions in natural host systems
No abstract available.
Authors
Claire E. Couch, Raquel Xavier, Brianna R. Beechler
Unique diet and Philonema sp. infections in reservoir-rearing juvenile Chinook Salmon Unique diet and Philonema sp. infections in reservoir-rearing juvenile Chinook Salmon
Objective Dams and reservoirs can alter juvenile growth and survival of migratory salmonids through several physical and biological mechanisms. Juvenile Chinook Salmon Oncorhynchus tshawytscha that are produced upstream of large hydropower dams may have associated passage mortality, but the reservoirs created by these dams can support rapid growth. Characterizing the biotic drivers of...
Authors
Marina S. Larson, Anindo Choudhury, Ethan N. Gardner, Peter Konstantinidis, Christina Amy Murphy, Michael L. Kent, James T. Peterson, Claire E. Couch
Gut microbiome composition associates with corticosteroid treatment, morbidity, and senescence in Chinook salmon (Oncorhynchus tshawytscha) Gut microbiome composition associates with corticosteroid treatment, morbidity, and senescence in Chinook salmon (Oncorhynchus tshawytscha)
Pacific salmon experience prolonged elevation in corticosteroid hormones during important life history events including migration, reproduction, and senescence. These periods of elevated corticosteroids correspond with changes to immunity and energy metabolism; therefore, fish may be particularly vulnerable to mortality at these times. Recent studies found that stress-induced cortisol...
Authors
Claire E. Couch, William T. Neal, Crystal L. Herron, Michael L. Kent, Carl B. Schreck, James T. Peterson
Effects of supplemental feeding on the fecal bacterial communities of Rocky Mountain elk in the Greater Yellowstone Ecosystem Effects of supplemental feeding on the fecal bacterial communities of Rocky Mountain elk in the Greater Yellowstone Ecosystem
Supplemental feeding of wildlife is a common practice often undertaken for recreational or management purposes, but it may have unintended consequences for animal health. Understanding cryptic effects of diet supplementation on the gut microbiomes of wild mammals is important to inform conservation and management strategies. Multiple laboratory studies have demonstrated the importance of...
Authors
Claire E Couch, Benjamin Wise, Brandon Scurlock, Jared D. Rogerson, Rebecca K. Fuda, Eric K Cole, Kimberly E Szcodronski, Adam Sepulveda, Patrick R. Hutchins, Paul C. Cross
Non-USGS Publications**
Polley, Tamsen & Couch, Claire & Leong, Connor & Peterson, James & Weiss, Louis & Takvorian, Peter & Kent, Michael. (2025). Laboratory transmission of Adult Salmon Enteritis and associated pathogens in juvenile Chinook Salmon (Oncorhynchus tshawytscha). 10.1101/2025.04.07.647091.
Carey, K. C., Kent, M., Schreck, C. B., Couch, C. E., Whitman, L., & Peterson, J. T. (2024). Influence of stream temperature and human disturbance on prespawn mortality of Chinook Salmon in the Willamette River basin. North American Journal of Fisheries Management, 44(5), 1147-1164.
Mani, A., Henn, C., Couch, C., Patel, S., Lieke, T., Chan, J. T., ... & Salinas, I. (2024). A brain microbiome in salmonids at homeostasis. Science Advances, 10(38), eado0277.
Schuster, C. J., Murray, K. N., Sanders, J. L., Couch, C. E., & Kent, M. L. (2024). Review of Pseudoloma neurophilia (Microsporidia): A common neural parasite of laboratory zebrafish (Danio rerio). Journal of Eukaryotic Microbiology, 71(5), e13040.
Tsuchida, D. Y., Gentzkow, M. F., Spaan, R. S., Burco, J., Couch, C. E., Spaan, J. M., ... & Beechler, B. R. (2024). Bighorn Sheep (Ovis canadensis) with Higher Whole Blood Selenium Levels Have Improved Survival and Altered Immune Responses. The Journal of Wildlife Diseases, 60(3), 721-726.
Larson, M. S., Choudhury, A., Gardner, E. N., Konstantinidis, P., Murphy, C. A., Kent, M. L., ... & Couch, C. E. (2024). Unique diet and Philonema sp. infections in reservoir‐rearing juvenile Chinook Salmon. Transactions of the American Fisheries Society, 153(3), 312-325.
Couch, C., Sanders, J., Sweitzer, D., Deignan, K., Cohen, L., Broughton, H., ... & Beechler, B. (2022). The relationship between dietary trophic level, parasites and the microbiome of Pacific walrus (Odobenus rosmarus divergens). Proceedings of the Royal Society B, 289(1972), 20220079.
Laliberte, C., Devan-Song, A., Burco, J. D., Couch, C. E., Gentzkow, M. F., Spaan, R. S., ... & Beechler, B. R. (2023). A simple biochemical plasma test as an indicator of maternal energy balance predicts offspring survival in bighorn sheep. Frontiers in Ecology and Evolution, 11, 1106635.
Couch, C. E., Neal, W. T., Herron, C. L., Kent, M. L., Schreck, C. B., & Peterson, J. T. (2023). Gut microbiome composition associates with corticosteroid treatment, morbidity, and senescence in Chinook salmon (Oncorhynchus tshawytscha). Scientific Reports, 13(1), 2567.
Couch, C. E., Peterson, J. T., & Heimowitz, P. (2023). Evaluating the institutional and ecological effects of invasive species prevention policy: a case study from the US Fish and Wildlife Service. Management of Biological Invasions, 14(2), 269-288.
Couch, C. E., Colvin, M. E., Chitwood, R. L., Peterson, J. T., & Schreck, C. B. (2022). Scope of the cortisol stress response in Chinook salmon during maturation. Fisheries Research, 254, 106416.
Schuster, C. J., Sanders, J. L., Couch, C., & Kent, M. L. (2022). Recent advances with fish microsporidia. In Microsporidia: Current Advances in Biology (pp. 285-317). Cham: Springer International Publishing.
Yarborough, E., Glidden, C., Coon, C., Couch, C., Sisson, D., Johns, J., ... & Beechler, B. (2022). Exploring the use of the erythrocyte sedimentation rate as an inflammatory marker for free-ranging wildlife: a case study in african buffalo (syncerus caffer). The Journal of Wildlife Diseases, 58(2), 298-308.
Couch, C. E., Kent, M. L., Weiss, L. M., Takvorian, P. M., Nervino, S., Cummins, L., & Sanders, J. L. (2022). Enterocytozoon schreckii n. sp. infects the enterocytes of adult chinook salmon (Oncorhynchus tshawytscha) and may be a sentinel of immunosenescence. Msphere, 7(1), e00908-21.
Couch, C. E., & Epps, C. W. (2022). Host, microbiome, and complex space: applying population and landscape genetic approaches to gut microbiome research in wild populations. Journal of Heredity, 113(3), 221-234.
Rothenberg, S. E., Sweitzer, D. N., Rackerby, B. R., Couch, C. E., Cohen, L. A., Broughton, H. M., ... & Beechler, B. R. (2021). Fecal methylmercury correlates with gut microbiota taxa in Pacific walruses (Odobenus rosmarus divergens). Frontiers in Microbiology, 12, 648685.
Couch, C. E., Stagaman, K., Spaan, R. S., Combrink, H. J., Sharpton, T. J., Beechler, B. R., & Jolles, A. E. (2021). Diet and gut microbiome enterotype are associated at the population level in African buffalo. Nature communications, 12(1), 2267.
Yang, C., Kari, L., Lei, L., Carlson, J. H., Ma, L., Couch, C. E., ... & Caldwell, H. D. (2020). Chlamydia trachomatis plasmid gene protein 3 is essential for the establishment of persistent infection and associated immunopathology. MBio, 11(4), 10-1128.
Couch, C. E., Arnold, H. K., Crowhurst, R. S., Jolles, A. E., Sharpton, T. J., Witczak, M. F., ... & Beechler, B. R. (2020). Bighorn sheep gut microbiomes associate with genetic and spatial structure across a metapopulation. Scientific reports, 10(1), 6582.
Couch, C. E., Movius, M. A., Jolles, A. E., Gorman, M. E., Rigas, J. D., & Beechler, B. R. (2017). Serum biochemistry panels in African buffalo: Defining reference intervals and assessing variability across season, age and sex. PLoS One, 12(5), e0176830.
Yang, C., Kari, L., Sturdevant, G. L., Song, L., Patton, M. J., Couch, C. E., ... & Caldwell, H. D. (2017). Chlamydia trachomatis ChxR is a transcriptional regulator of virulence factors that function in in vivo host–pathogen interactions. Pathogens and Disease, 75(3), ftx035.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Historical (1900s-1940s) and present-day (2003 – 2023) spring Chinook salmon (Oncorhynchus tshawytscha) spawning distribution in the Willamette River Basin, Oregon Historical (1900s-1940s) and present-day (2003 – 2023) spring Chinook salmon (Oncorhynchus tshawytscha) spawning distribution in the Willamette River Basin, Oregon
Spawning distribution maps for Upper Willamette River (UWR) spring Chinook salmon were created for the historical period (approximately 1910-1940), and for the present-day period (2003-2023). These maps were created as a tool to visualize generalized, reach-scale patterns of spawning distribution before and after the construction of high-head dams and other large-scale anthropogenic...
Acoustic-tagged juvenile Chinook salmon (Oncorhynchus tshawytscha), steelhead (O. mykiss), and sockeye salmon (O. nerka) detections in the Yakima River, Washington, 2018-2024 (version 1.1, September 2025) Acoustic-tagged juvenile Chinook salmon (Oncorhynchus tshawytscha), steelhead (O. mykiss), and sockeye salmon (O. nerka) detections in the Yakima River, Washington, 2018-2024 (version 1.1, September 2025)
Juvenile Chinook salmon (age 0 and age 1), steelhead, and sockeye salmon were tagged with acoustic transmitters and released at sites along the Yakima River in and below Yakima, WA from 2018 to 2024. Detection sites varied across years but included arrays placed at diversion dams, canals, hydropower facilities, and other locations throughout the Yakima and Columbia rivers. Study design...